crash sync question re "sweep" knob

[slotbot]

HI.

I just finished my crash sync and it sounds awesome. The only thing i have noticed with it is that the "sweep" knob or whatever you want to call it only causes changes over about half the range of the pot. after roughly half way it has (as far as i can tell) the same sound.

im using a 100K linear pot. should it be log? the schematic dosnt specify. I rechecked the values of parts and they all look ok.

Has anyone else experianced this problem? or is it not really a "problem" ie thats  just the way the design is.

THANKS  

scott.

[jmusser]

I just checked my circuit, and I used a linear for the "gargle" pot on mine. I believe mine does a little of the same thing that you're talking about (as far as sweep), but I believe that's about what you can expect using a conventional pot. The "gargle" pot is for a foot pedal, and probably if you used a Hot potz II in the place of the linear pot, it would act like it's supposed to. This is still something I need to do. I'm hoping to modify my wah pedal and Gargletron, so I can switch from the panel mount pot of the Gargletron, to the wah pedal pot for expression. It's just finding the time for it. This circuit was frustrating to me, because I had no idea that the "gargle" pot was actually supposed to be what swept for the talking sound. I was unfamiliar with this circuit, so I assumed it was triggered like an auto-wah, by the attack of the pick on the strings. Wrong!

[sovtek50]

I'd like to take this opportunity to stand up and say the Crash Sync is a hell of a stompbox and one of the best non-commercially available designs ever, imo. It has become sort of a signature sound of my work as a guitarist with a German major-deal (whoaaah!) weird guitar/electronic pop band. I took it on tour and used it on the recording of the latest single. (Damn, I must not forget to send John Hollis a copy.) After that, I had to built one for the recording engineer at the studio, the live sound engineer of the band...ah yes, and for the tour bus driver also.
Now to Your problem...
You need to use a reverse log pot for it. Since these are sometimes hard to find, You can also use a normal log pot and wire it the other way round. Now the pot will work backwards, but smoothly.

[jmusser]

I will second the Crash Sync. The Ugly Face gets a lot of press on the forum, and it is a great effect, don't get me wrong. The Crash Sync is absolutely awesome, and has an incredible amount of versitility. The down octave feature is not even mentioned in the text, and it has one of the better one and two octaves down you'll hear on any circuit. Hook it up to an expression pedal, and you've got Star Wars light sabors from Hell! The sustain is endless, and I would put it up against any other circuit out there.

[guitarhacknoise]

YEAH!
I etched & drilled a crash-sync board last night.
Love the sound clips, but you know how that goes...........
seems like most tone mangler effects only sound usefull in a few knob positions while the rest is crap.  These reviews definately make me believe that this lil' octave/noise jammer is a team of horses chasing down that one trick pony.
blah blah blah, ramble ramble ramble........
Anyway.... can't wait to hear it for real.
gonna go pull all the resisters and get goin'

-matthias

p.s.
SOVTEK 50....... P.M. me more info on band.

[RDV]

I just built mine and recorded a sample of the freq sweep and low octave functions. Does this sound right? Crash Sync

RDV

[jmusser]

Yeah Baby!! That's her! What do you think? There are features of this circuit that I like over and above any I've ever built, even including the Ugly Face. That's saying something, because it's a great circuit in and of it's self. Have you separated the octaves and played around with them yet? I left mine unhooked in a baggie inside a shoe box last week, and I'm sure if I unzip it, it'll still be sustaining the note I stopped on.

[guitarhacknoise]

I just finished twiddlin' the knobs on mine,  Lots of fun!
SIck sustain! and that "phasey octave thing"
I used a 4558 and a cmos 555
Two substitutions:
240pF for the 330pF  and
100k linear pot instead of the trim pot.

Now to find a Treadle!

So, Who wants to take a shot at explaining HOW the crash sync works?

And what about utilizing pin 5 of the 555?

-matthias

[newperson]

HI,

Could someone explain how to wire this pedal up. And tell me the values for the pots?  I see depth 1 and depth 3 and a 100k trimmer.  Should the trimmer be mounted off the board?  I am still too new to know how this wires up without directions.  Is the depth 2 the trimmer?

Thanks,
Paul.

[Connoisseur of Distortion]

you're supposed to use that as a treadle??? i just thought it worked like a wonderful tone control! 

[newperson]

Hello again,

Could someone explain how to wire this pedal up. And tell me the values for the pots?  I see depth 1 and depth 3 and a 100k trimmer.  Should the trimmer be mounted off the board?  I am still too new to know how this wires up without directions.  Is the depth 2 the trimmer?

Paul.

[newperson]

More digging has led me to (two) 100K log pots for the depth controls.  I see 1 and 2 listed and a 100k trimmer.  But I still cannot see how to apply them to the layout. 

paul.

[sovtek50]

Okay, here comes help. The names of the controls are somewhat misleading. "Depth" is really Volume. Connect 1 and 3 to the pot, 2 (the wiper of the pot) is the effect's output.
The Trimpot (is it called "Gargle"?) should be named "Filter" or "Freq", it changes the sound in a strange way. Use an ordinary 100k log pot like this (if I remember i correctly):2 and 3 connected together got to pin 6 of the 555 chip, lug 1 goes to pin 7 and the 4k7 resistor.

(If  the sound doesn't change smoothly, then it's 1 and 2 soldered together and connected to pin 6 and lug 3 to pin 7)

[newperson]

Hey thanks sovtek50,

I had to order the rest of the parts to finish this.  I will try out the way you said to wire it when they come in and report back. 

Paul.

[newperson]

Up and running.  Thank you for the help with the wiring.  I sometimes have a bit of noise with it bypassed.   It comes and goes.  Perhaps it will go away after I put it in a box.  I do not see how it makes the noise in the bypass though.   Is a tl072cp and a lm555cn ok for the chips.  It works fine and is loud with these two.  The sound holds for a long time then suddenly stops dead quiet.  Like it has a lower volume threshold? 

Now if I could get the Sample and Hold filter to work everthing would be fine for me.
Paul.

[Connoisseur of Distortion]

i recommend a volume control on the front end of this pedal, as well. call it 'drive'. backing off of it will make it less gainy and cut out sooner, which is good to use for synthy sounds.

[newperson]

How would you wire that?
Paul.